Temporary Environmentally Controlled Enclosure For Pipeline Repair

ABSTRACT

This invention relates to a climate controlled, air supportable, temporary elongated enclosure constructed around a predetermined section of transmission pipeline having at least one anomaly that needs to be inspected, repaired, or both. The enclosure allows workers to inspect and repair an anomaly in the pipeline without regard to normal weather conditions.

FIELD OF THE INVENTION

This invention relates to a climate controlled, air supportable, temporary elongated enclosure constructed around a predetermined section of transmission pipeline having at least one anomaly that needs to be inspected, repaired, or both. The enclosure allows workers to inspect and repair an anomaly in the pipeline without regard to normal weather conditions.

BACKGROUND OF THE INVENTION

The nation's more than 2.6 million miles of pipelines safely deliver energy related commodities, such as trillions of cubic feet of natural gas, and hundreds of billions of ton/miles of liquid petroleum products each year. These pipelines are essential because of the enormous volumes of commodity energy products they move each day which is well beyond the capacity of other forms of transportation, such as by rail or by road. A transmission pipeline, also sometimes referred to as a mainline pipeline, is the principle pipeline in a given system. They are typically between about 16 and 48 inches in diameter. Pipelines are one of the safest and most effective ways of transporting petroleum and natural gas from the wellhead to processing plants. However, pipeline operators are under substantial financial and environmental pressures to avoid incidents that can cause a commodity release. Therefore, the integrity of such pipelines is of very high priority, not only for pipeline companies and governmental bodies, but also for people and businesses that live and operate in the vicinity of such pipelines. Various standards are required by governmental agencies and, as such, all such pipelines transporting energy products are required to undergo integrity inspection on a continual basis.

Transmission pipelines can be subjected to a variety of anomalies, including but not limited to, external corrosion, internal corrosion, metal loss, exterior and interior stress corrosion cracking, external damage, manufacturing defects, and construction defects. Transmission pipelines, most of which are buried underground, are typically inspected by the use of an instrument referred to as a “smart pig” which is placed in the pipeline and carried along with the flowing product. A smart pig is an inspection device comprised of a collection of sophisticated, primarily electronic, instruments powered by on-board batteries. The instruments collect and transmit data relating to any detected anomalies, particularly those that have the potential of jeopardizing the integrity of the pipeline. Non-limiting examples of such sophisticated instruments include a gps device, various sensors, including an ultra-sonic transmitter, as well as magnetic devices. If any anomalies are sensed, the corresponding data is transmitted to an operator as well as to a suitable data collection and storage device, as to the type of anomaly and its location. The precise location of the anomaly is targeted via gps coordinates.

A work crew is then sent to the designated location to excavate a targeted section of pipeline containing the anomaly. Although any length section of pipeline can be targeted and excavated at any given time, it is standard practice in some areas of the country to excavate a 60 ft to 80 ft. long section of pipe containing one or more identified anomalies. Once the targeted section of pipeline is excavated and exposed, the pipe surface is cleaned for inspection and repair. For example, after excavation, the targeted section pipeline will typically contain a layer of scale, including old coating material, which will need to be removed before proper inspection and repair can be performed.

One substantial problem that an inspection/repair crew often faces is sweating or icing of the exposed targeted section of pipeline—depending on season and location of the pipeline. The primary cause of sweating results when the outside surface of the pipe is colder than the temperature than the surrounding atmosphere, particular in hot humid locations. Rain, or snow, can result in icing of the exposed pipeline section in colder locations. When these conditions occur, work, such as sandblasting and recoating of a repaired section of pipeline, cannot be performed. It is customary that the crew wait until the next day at which the relative humidity is low enough so that sweating does not occur, or is warm enough to melt any icing formation before proper inspection and repair can resume. Needless to say, this presents a significant added cost for the pipeline operator. It also prolongs the repair of an anomaly that can result in a pipeline failure.

Thus, there is a significant need in the art for systems that allow work crews to excavate, inspect, and repair targeted sections of pipeline—regardless of normal weather conditions.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided: a flexible, air supportable, elongated enclosure, constructed 360 degrees about an excavated, targeted section of pipeline to be inspected, repaired, or both, and which targeted section of pipeline has a starting point and an ending point wherein the distance between the starting point and the ending point defines the length of said targeted section, wherein at both the starting point and the ending point said elongated enclosure is sealingly, but removably, secured to the said targeted section of pipeline, thereby resulting in an elongated enclosure containing an environmentally protected interior space that is sealed to the outside environment and containing the entire targeted section of pipeline, wherein the environmentally protected interior space within said tubular enclosure is of sufficient size capable of allowing the required number of work-crew members to perform the necessary work needed to inspect and repair said targeted section of pipeline, wherein there is also provided: i) at least one transparent panel to allow natural light to enter said interior space and to observe work being done inside of said enclosure; ii) a climate control system capable of providing a flow of air into said interior space, which air has been controlled with respect to relative humidity, temperature, and flow rate; iii) at least two conduits to conduct said climate controlled air from said climate controlled system into said enclosure; and iv) at least one door providing ingress and egress to and from said interior space.

In a preferred embodiment of the present invention the enclosure is constructed from a material that is: a) cloth-like; b) substantially waterproof; c) flexible enough to allow the enclosure to take its intended shape with use of forced air; d) strong enough to withstand the activities of workers preforming the needed work to inspect and repair said targeted section of pipeline; and e) easily removably fastened together by use of a suitable fastening means.

In another preferred embodiment, the material of which the enclosure of the present invention is constructed is a woven polyester material, coated with nylon or a polyvinyl chloride material for waterproofing.

In another preferred embodiment of the present invention the fastening means is a hoop and loop system.

In yet another preferred embodiment of the present invention the fastening means is a zipper.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 hereof is a representation of a targeted section of transmission pipeline that is being excavated for inspection, and repair, if necessary. Earth will also be removed from underneath the pipe section to allow workers to access the underside of said targeted section of pipeline.

FIG. 2 hereof is a representation of a top view of a preferred enclosure of the present invention which is constructed, on-site, around a targeted section of transmission pipeline to be inspected and repaired. A climate control system CCS is also shown providing a dehumidified and predetermined temperature to the enclosure. Air from the climate control system will also be of an effective volume and rate to provide structural support for the enclosure.

FIG. 3 hereof is a cross-sectional view along line 3-3 of FIG. 2 hereof of and looking to the climate controlled air input end of the enclosure. This Figure shows the enclosure being large enough to enclose a 20 ft to 80 ft section of pipeline to be serviced. Also shown are several workers inspecting and repairing the targeted section of pipeline.

FIG. 4 hereof is a cross-sectional view along line 4-4 of FIG. 2 hereof showing a door for ingress and egress to and from the interior of the enclosure. Also shown are input and output ports for allowing for climate-controlled air to be recycled into and out of the enclosure to help support the enclosure structure, as well as to provide a relatively dehumidified/temperature-controlled interior which helps prevent sweating and condensation on the exterior surface of the targeted section of pipe.

FIG. 5 hereof is an outside view of the end of the enclosure opposite the air input end and showing the enclosure material creating a seal around the pipeline end view of a finished elongated enclosure of the present invention constructed around a targeted section of pipeline.

FIG. 6a hereof is an end view a zipper/hook & loop system that is used to fasten panels and sections of an enclosure of the present invention. This view shows a hook & loop system in an open position.

FIG. 6b hereof is an end view of the zipper/hook & loop system in a closed position securing the zipper from accidentally opening.

FIG. 7 hereof is a view of the air flow from the climate control system into the enclosure and exhausted though a plurality of vents located in the sides of the enclosure.

DETAILED DESCRIPTION OF THE INVENTION

As previously mentioned, pipeline maintenance and repair companies have evaluation processes for maintaining transmission pipelines, including but not limited to the use of so-called smart pigs. A smart pig measures several different elements from inside the pipeline, inter alia, restrictions and deformations, metal loss, as well as other anomalies. Once these anomalies are found and recorded, the company will then identify the exact location of such anomalies in the pipeline. Use of the present invention alleviates a costly and time-consuming problem often encountered by work crews sent to inspect and repair targeted sections of pipeline. The problem being sweating or icing of the exterior surface of exposed pipeline, which prevents certain important work to be done until more favorable weather conditions occur. Such work as sandblasting and recoating of the pipe surface after repair. While sweating, condensation, and icing are mentioned here when describing conditions on the pipe surface that will prevent certain work from being done, it is to be understood that any condition that will cause the pipe surface to be wet or icy needs to be avoided.

Any suitable size trench can be dug when excavating the targeted section of pipeline as long as it is at least as long as the targeted section of pipeline. The excavation must also be large enough to accommodate an enclosure of a size that will allow for a typical work crew to inspect and repair the identified anomaly in the pipe section within the interior space of the enclosure free from normal inclement normal weather conditions. The term “normal weather conditions” as used herein means a typical day depending on the location and season. This excludes severe weather conditions that can have the potential of posing a danger to worker, as well as undesirable damage to the enclosure. Non-limiting examples of such severe weather conditions include hurricanes, tornados, and the like. A typical excavation about a targeted section of pipeline will generally be from about 60 ft to about 80 ft long, 12 ft wide, and 8 ft deep, although location circumstance may require dimensions larger or smaller. The exact dimensions of the excavation is not critical to the instant invention as long as the designated one or more anomaly can be inspected and repaired. The larger size excavation will give a work crew adequate room to inspect and repair an anomaly located at any point around the entire exposed surface of the section of pipeline. Since the excavated pipe will typically contain a relatively heavy layer of scale, it is desired that this scale be removed. A portion of the scale will typically include tar-based coating material that was applied to the surface of the pipe for protection before being buried. This tar-based coating is generally removed by chipping it away by use of a hammering or chiseling tool. Sandblasting of any remaining scale is often required. Once the targeted section of pipeline is repaired, it is then recoated before being reburied. The coating used must have resistance to such things as root growth, soil bacteria, moisture, salts, acids and extreme temperatures. The most commonly used coatings to protect transmission pipelines include coal tar enamel, with or without an epoxy primer. Such a coating cannot be applied if the outside surface of the pipe is wet. It is to be understood that this invention is not limited to the coating material that is used to recoat the section of repaired pipeline. Any material suitable for such use can be used.

Use of the present elongated climate-controlled enclosure allows a work crew to inspect and repair a targeted section of transmission pipeline in substantially any normal weather condition. When the enclosure of the present invention is used, a work crew will not have to waste time and money waiting for a day when the relative humidity, or overall weather condition, is suitable for inspecting a performing the required work needed to repair any anomaly on a targeted section of pipeline.

The present invention will be better understood with reference to the figures hereof. FIG. 1 hereof is an illustration of a targeted section of a transmission pipeline P being excavated and which sits in an earthen ditch ED. As previously mentioned, a typical excavation will be from about 60 ft to about 80 ft long, by about 12 ft wide and about 8 ft deep. Dirt will also be cleared to a predetermined distance beneath the pipeline so that workers will be able to service the entire circumference of the exposed pipe section. It is to be understood that although this application is written primarily for the larger transmission pipelines, also sometimes referred to as mainline, this invention also applies to smaller diameter pipeline such as interstate and gathering pipelines that face the same predicament with regard to anomalies that can present a risk to the integrity of the pipeline.

FIG. 2 hereof is an elevated view of the top of one preferred embodiment of an elongated enclosure E of the present invention. At least one door D is provided at an end of said enclosure E, as well as at least one door (not shown in this Figure) on at least one side. It is preferred that at least two doors be provided on each side of the enclosure, which doors will be strategically located to enable workers to exit in case of an emergency. The doors will be held closed with use of a suitable fastening system that is easily fastened and unfastened, such as a hook and loop system, a zipper system, or a pressed rod-in-groove system. Preferred is the use of a hook and loop system. Also illustrated in FIG. 2 hereof is a climate control system CCS which conducts climate-controlled air through conduits C1 and C2 to the interior of the enclosure E. Climate control system CCS can be any suitable air handling system, such as the well-known HVAC systems. For purposes of the present invention, such a system can be referred to as a DHVAC system because the goal of such a system is to provide relatively low humidity (dehumidified), temperature controlled air that helps prevent sweating of the pipe surface of the targeted section of pipeline. Controlling the temperature of the air conducted in the interior of enclosure, by either heating or cooling, also provides a more favorable work environment for the workers, as well as aiding in preventing the pipe surface from sweating. Window panels WIN are provided throughout the enclosure for both lighting purposes as well as for safety to enable observation into the enclosure, particularly during the repair and recoating process.

FIG. 2 hereof also shows vents V for exhausting air from the enclosure and a support cable system SC comprised of a cable of suitable material, such as wire rope, which is passed through a plurality of fabric loops which at its closed end are secured to the enclosure material. This aids in both the early construction stage of the enclosure as well as providing another means (other than forced air) of holding the enclosure in place at the correct height. The support cable system is anchored in place by the use of anchors A at both ends of said enclosure.

FIG. 3 hereof is a cross-sectional view of the enclosure of FIG. 2 hereof along line 3-3. All elements appearing in this figure that are common to any previous figure hereof will have the same identifier. This figure shows a plurality of vents V for exhausting air from said enclosure. The flow of controlled air entering the enclosure from climate control system CCS and being exhausted from the enclosure via vents V can easily be calculated and controlled by those having at least ordinary skill the art as to flow rate, flow volume, temperature, and relative humidity. Thus, the number and size of both input ports and exhaust vents will depend on such things as the final size of the enclosure, atmospheric conditions outside of the enclosure, and the number of workers located inside the enclosure. Also shown in FIG. 3 hereof are a plurality of windows preferably comprised of clear plastic and are a section of a panel or door.

FIG. 4 hereof is a cross-sectional view along line 4-4 of FIG. 2 hereof looking toward the controlled air intake end of the enclosure. Intake conduit ports C1 and C2 are shown as well as pipeline P, door D as well as support cable system SC and anchors A.

FIG. 5 hereof is a view of the exterior end of an enclosure of the present invention opposite the end where climate control air enters the enclosure. This FIG. 5 shows a seal S where the enclosure is secured to the pipeline. The seal, which is preferably leakproof, can be provided by any suitable means, such as by wrapping the enclosure material around the pipe and sealing it to the pipe using any suitable non-permanent sealing means. Non-limiting examples of suitable non-permanent sealing means include industrial tape, such a gorilla tape, tie wraps, and nylon straps with cam buckles.

The manner in which an enclosure of the present invention is constructed is not critical as long as: it is capable of being supported by a flow of forced air; it be substantially weather proof; it contain a plurality of window panels on both the top as well as the sides; that it contain multiple doors, one of which is at an end of the enclosure and at least one at the sides; and that be large enough to house the entire targeted section of pipeline and accommodate a work crew with their required tools for inspecting and repairing the targeted section of pipeline.

In a preferred embodiment, the overall enclosure is constructed of several main sections, such as a roof section, a floor section, 2 side sections, and 2 end sections. Each section is comprised of a plurality of panels of a suitable industrial strength flexible material. The term “industrial strength” as used herein means it's most commonly used meaning that it be so strong and durable as to be suitable for industry. Flexible industrial strength materials suitable for use herein include those that are: a) cloth-like, b) substantially waterproof, c) flexible enough to allow it to take the desire elongated form by use of forced air; d) strong enough to withstand the activities of a work crew performing required types of work and equipment needed to inspect, repair, and coat an exposed targeted section of pipeline; and e) that it be of a material that can be easily removably joined together by use of suitable joining means. A preferred material of which the enclosures of the present invention are comprised are woven polyester material, coated with nylon or a polyvinyl chloride material for waterproofing. Preferred is a woven polyester material coated with polyvinyl chloride.

Non-limiting examples of joining means that can be used in the practice of the present invention for removably joining panels together, or for joining sections of the enclosure together include: hook and loop fasteners, such as those available under the tradename “Velcro”, industrial strength zippers, magnetic fasteners, metal or plastic snaps, zippers, and the like. Preferred fasteners are the hook and loop fasteners and zippers, particularly industrial strength hook and loop fasteners and zippers. More preferred, especially when joining sections together, as well as for doors, is when a hook and loop system is used in combination with a zipper section, as illustrated in FIGS. 6a and 6b hereof. That is, when both a zipper system and the hook and loop system are aligned substantially parallel at the vicinity of the edge of the panel, or section. For example, the hood and loop system will be closest to the outer edge (½ to 2 inches) and the zipper system will be about 1 to 2 inches from the hook and loop system. It is preferred that only the hook and loop fastening system be used only when fastening the panels together. FIGS. 6a and 6b are illustrations of a combination zipper/hook and loop system to secure panels and sections together. FIG. 6a shows the combination system wherein the zipper Z is zipped shut and in a closed position wherein the hook and loop system HL is not yet closed and locked in place. EN is an enclosure section to which the the fasteners are applied. FIG. 6b shows the hook and loop system pressed together and thus locked in place and securing the locked zipper.

Although the panels used to fabricate the sections of the enclosure of the present invention can be any shape, it is preferred that they be rectangular, primarily for ease of construction.

FIG. 7 hereof is a diagram of the air flow in and out of an enclosure of the present invention. For example, climate-controlled air from the climate control system CCS enters the enclosure at C1 and C2 and air within the enclosure is exhausted to the atmosphere via vents V. 

What is claimed is:
 1. In accordance with the present invention there is provided: a flexible, air supportable, elongated enclosure, constructed 360 degrees about an excavated, targeted section of pipeline to be inspected, repaired, or both, and which targeted section of pipeline has a starting point and an ending point wherein the distance between the starting point and the ending point defines the length of said targeted section, wherein at both the starting point and the ending point said elongated enclosure is sealingly, but removably, secured to the said targeted section of pipeline, thereby resulting in an elongated enclosure containing an environmentally protected interior space that is sealed to the outside environment and containing the entire targeted section of pipeline, wherein the environmentally protected interior space within said tubular enclosure is of sufficient size capable of allowing the required number of work-crew members to perform the necessary work needed to inspect and repair said targeted section of pipeline, wherein there is also provided: i) at least one transparent panel to allow natural light to enter said interior space and to observe work being done inside of said enclosure; ii) a climate control system capable of providing a flow of air into said interior space, which air has been controlled with respect to relative humidity, temperature, and flow rate; iii) at least two conduits to conduct said climate controlled air from said climate controlled system into said enclosure; and iv) at least one door providing ingress and egress to and from said interior space.
 2. The elongated enclosure of claim 1 wherein the material of which the enclosure if constructed is: a) cloth-like; b) substantially waterproof; c) flexible enough to allow the enclosure to take its intended shape with use of forced air; d) strong enough to withstand the activities of workers preforming the needed work to inspect and repair the targeted section of pipeline; e) easily removable fastened together by use of a suitable fastening means.
 3. The enclosure of claim 2 wherein the material is a woven polyester material, coated with nylon or a polyvinyl chloride material for waterproofing.
 4. The enclosure of claim 2 wherein the fastening means is a hoop and loop system.
 5. The enclosure of claim 2 wherein the fastening means is a zipper.
 6. The enclosure of claim 2 wherein the fastening means is a combination of a hoop and loop system and a zipper system.
 7. The enclosure of claim 1 which is comprised of plurality of rectangular panels of materials defined in claim
 1. 8. The enclosure of claim 1 wherein the enclosure is comprised of 4 main sections, a floor, a roof, and 2 sides each of which is constructed from a plurality of panels as defined in claim 7 hereof. 